10 Biggest Unexplained Mysteries Of The Universe

9. ‘Oumuamua

Even if we have no hard evidence that there is other life in the universe, that doesn't mean there aren't suggestions for it.

In 2017, astronomers in a Hawaiian Observatory spotted an unexpectedly quick object hurtling through our solar system. It didn't look like a regular asteroid and didn't have any of the properties that would suggest it was a comet, yet it was accelerating past us and around the sun, where it will continue traveling until it leaves our little corner of space.

Calculations made about its speed and trajectory suggested that it could have been knocked out of the Sun's deep orbit or that it could have been the remains of a comet from outside our solar system, but in all of these theories there was something that didn't add up.

Naturally this led speculators to think about the possibility that it had other origins, perhaps being some form of solar-powered alien spacecraft. At first that might sound like just another conspiracy theory but the evidence put forward by Avi Loeb of Harvard University has convinced many scientists that this may actually be the case.

In July 2019, other astronomers reported that 'Oumuamua was of "purely natural origin" but that hasn't stuck with a lot of Loeb's followers.